WWW- A former gay porn director who was the executive producer of Michael Jackson's "What More Can I Give" benefit concert in 2001 may find himself being investigated by the California attorney general in 2006.

Fred Marc Schaffel, a one-time smut sultan and pal of Jackson, is under the heavy scrutiny of Hollywood private investigator Paul Barresi. Just last week, Barresi sent a letter to California AG Bill Lockyer, urging him to delve into alleged shady fund-raising by Schaffel.

Barresi claims he has information that Schaffel never registered or provided financial reports to the attorney general's office - a fiduciary requirement - for donations made to Jackson's D.C.-staged benefit for the families of 9/11 victims.

The concert - which featured performers including James Brown, Mariah Carey, Justin Timberlake and Destiny's Child - reportedly raised $2 million for relief charities. But an accompanying "What More Can I Give" single - which Jackson boasted would raise $50 million for the charities - and an album of the same title that Schaffel was supposedly producing and had raised money for, were never released.

In 2002, the Dallas Observer revealed that Schaffel was also "Marc Fredrics," the director of such gay porn flicks as "Cocktales" and "The Man with the Golden Rod." The paper further reported that Schaffel was a longtime associate of the boy-crazy Jackson, who hired him in late 2000.

"He's just a con man - he's cheated everybody, keeps the proceeds [to events] and never reports them to the state," Diane Dimond - who produced a three-part expose series on Schaffel for Court TV back in 2002 - told PAGE SIX. (Dimond also authored the Jackson tell-all book, "Be Careful Who You Love.")

Barresi, who was hired by Court TV to investigate Schaffel in 2001, added, "He is a career scam artist."

Schaffel's lawyer, Thomas Byrne, shot back: "I have no idea what he's talking about. This Barresi guy - I don't know what kind of a private investigator he is. It's a ridiculous accusation."

As for Dimond, "I'm not surprised she's backing Barresi. She's been after Schaffel before," Byrne said.